Rename REAMDE to README.md
[nit.git] / src / parser_util.nit
index 91e766d..cd4f205 100644 (file)
@@ -30,7 +30,7 @@ redef class ToolContext
 
                var eof = tree.n_eof
                if eof isa AError then
-                       self.fatal_error(null, "Fatal Error: {eof.message}")
+                       self.fatal_error(null, "Fatal Error: {eof.message}.")
                        abort
                end
                return tree.n_base.as(not null)
@@ -43,7 +43,7 @@ redef class ToolContext
                var nmodule = parse_module(string)
                var nclassdefs = nmodule.n_classdefs
                if nclassdefs.length != 1 then
-                       self.fatal_error(null, "Fatal Error: not a classdef")
+                       self.fatal_error(null, "Fatal Error: not a classdef.")
                        abort
                end
                return nclassdefs.first
@@ -57,7 +57,7 @@ redef class ToolContext
                var nclassdef = parse_classdef(mod_string)
                var npropdefs = nclassdef.n_propdefs
                if npropdefs.length != 1 then
-                       self.fatal_error(null, "Fatal Error: not a propdef")
+                       self.fatal_error(null, "Fatal Error: not a propdef.")
                        abort
                end
                return npropdefs.first
@@ -69,7 +69,7 @@ redef class ToolContext
        do
                var mod_string = "do\n{string}\nend"
                var nmodule = parse_module(mod_string)
-               var nblock = nmodule.n_classdefs.first.n_propdefs.first.as(AMainMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(ADoExpr).n_block.as(not null)
+               var nblock = nmodule.n_classdefs.first.n_propdefs.first.as(AMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(ADoExpr).n_block.as(not null)
                return nblock
        end
 
@@ -79,10 +79,24 @@ redef class ToolContext
        do
                var mod_string = "var dummy = \n{string}"
                var nmodule = parse_module(mod_string)
-               var nexpr = nmodule.n_classdefs.first.n_propdefs.first.as(AMainMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(AVardeclExpr).n_expr.as(not null)
+               var nexpr = nmodule.n_classdefs.first.n_propdefs.first.as(AMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(AVardeclExpr).n_expr.as(not null)
                return nexpr
        end
 
+       # Parse a super class declaration
+       # Fatal error if the `string` is not a syntactically correct super class declaration
+       fun parse_superclass(string: String): APropdef
+       do
+               var mod_string = "class Dummy\nsuper {string}\nend"
+               var nclassdef = parse_classdef(mod_string).as(AStdClassdef)
+               var nsuperclasses = nclassdef.n_propdefs
+               if nsuperclasses.length != 1 then
+                       self.fatal_error(null, "Fatal Error: not a super class declaration.")
+                       abort
+               end
+               return nsuperclasses.first
+       end
+
        # Try to parse the `string` as something
        #
        # Returns the first possible syntacticaly correct type among:
@@ -93,6 +107,15 @@ redef class ToolContext
        # - a block of statements `ABlockExpr`
        # - a full module `AModule`
        # - a `AError` if nothing else matches
+       #
+       #     var tc = new ToolContext
+       #     assert tc.parse_something("foo") isa TId
+       #     assert tc.parse_something("foo[bar]") isa AExpr
+       #     assert tc.parse_something("Foo[Bar]") isa AType
+       #     assert tc.parse_something("foo\nbar") isa ABlockExpr
+       #     assert tc.parse_something("fun foo do bar\nfoo") isa AModule
+       #     assert tc.parse_something("fun fun") isa AParserError
+       #     assert tc.parse_something("?%^&") isa ALexerError
        fun parse_something(string: String): ANode
        do
                var source = new SourceFile.from_string("", string)
@@ -111,18 +134,19 @@ redef class ToolContext
                tree = (new Parser(lexer)).parse
                eof = tree.n_eof
                if not eof isa AError then
-                       var ntype = tree.n_base.n_classdefs.first.n_propdefs.first.as(AMainMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(AVardeclExpr).n_type.n_types.first
+                       var ntype = tree.n_base.n_classdefs.first.n_propdefs.first.as(AMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(AVardeclExpr).n_type.n_types.first
+                       ntype.parent = null
                        return ntype
                end
                error = eof
 
                lexer = new Lexer(source)
                var first = lexer.next
-               if not first isa EOF then
-                       var second = lexer.next
-                       if second isa EOF and not second isa AError then
-                               return first
-                       end
+               if first isa EOF then return first
+               var second = lexer.next
+               if second isa EOF and not second isa AError then
+                       first.parent = null
+                       return first
                end
 
                lexer = new InjectedLexer(source)
@@ -134,18 +158,23 @@ redef class ToolContext
                tree = (new Parser(lexer)).parse
                eof = tree.n_eof
                if not eof isa AError then
-                       var nexpr = tree.n_base.n_classdefs.first.n_propdefs.first.as(AMainMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(AVardeclExpr).n_expr.as(AParExpr).n_expr
+                       var nexpr = tree.n_base.n_classdefs.first.n_propdefs.first.as(AMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(AVardeclExpr).n_expr.as(AParExpr).n_expr
+                       nexpr.parent = null
                        return nexpr
                end
                if eof.location > error.location then error = eof
 
                lexer = new InjectedLexer(source)
                lexer.injected_before.add new TKwdo
+               lexer.injected_before.add new TEol
+               lexer.injected_after.add new TEol
                lexer.injected_after.add new TKwend
                tree = (new Parser(lexer)).parse
                eof = tree.n_eof
                if not eof isa AError then
-                       var nblock = tree.n_base.n_classdefs.first.n_propdefs.first.as(AMainMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(ADoExpr).n_block.as(not null)
+                       var nblock = tree.n_base.n_classdefs.first.n_propdefs.first.as(AMethPropdef).n_block.as(ABlockExpr).n_expr.first.as(ADoExpr).n_block.as(ABlockExpr)
+                       nblock.n_kwend = null # drop injected token
+                       nblock.parent = null
                        return nblock
                end
                if eof.location > error.location then error = eof
@@ -160,12 +189,48 @@ redef class ToolContext
 
                return error
        end
+
+       # Parse the input of the user as something
+       fun interactive_parse(prompt: String): ANode
+       do
+               var oldtext = ""
+
+               loop
+                       printn prompt
+                       printn " "
+                       var s = sys.stdin.read_line
+                       if s == "" then continue
+                       if s.chars.first == ':' then
+                               var res = new TString
+                               res.text = s
+                               return res
+                       end
+
+                       var text = oldtext + s + "\n"
+                       oldtext = ""
+                       var n = parse_something(text)
+
+                       if n isa AParserError and n.token isa EOF then
+                               # Unexpected end of file, thus continuing
+                               if oldtext == "" then prompt = "." * prompt.length
+                               oldtext = text
+                               continue
+                       end
+
+                       return n
+               end
+       end
 end
 
+# A modified lexer that feed tokens before and after the real tokens.
 class InjectedLexer
        super Lexer
 
+       # The tokens to use before the real tokens (in order).
        var injected_before = new List[Token]
+
+       # The tokens to use after the real tokens (in order).
+       # The real EOF token is produced after these tokens.
        var injected_after = new List[Token]
        private var is_finished = false
 
@@ -173,7 +238,6 @@ class InjectedLexer
        do
                if not injected_before.is_empty then
                        var tok = injected_before.shift
-                       if tok._location == null then tok._location = new Location(file, 1, 1, 1, 0)
                        return tok
                end
                if not is_finished then
@@ -184,50 +248,6 @@ class InjectedLexer
                end
 
                var tok = injected_after.shift
-               if tok._location == null then tok._location = new Location(file, 1, 1, 1, 0)
                return tok
        end
 end
-
-redef class ANode
-       # Return an array of tokens that match a given text
-       fun collect_tokens_by_text(text: String): Array[Token]
-       do
-               var v = new CollectTokensByTextVisitor(text)
-               v.enter_visit(self)
-               return v.result
-       end
-
-       # Return an array of node that are annotated
-       # The attached node can be retrieved by two invocation of parent
-       fun collect_annotations_by_name(name: String): Array[AAnnotation]
-       do
-               var v = new CollectAnnotationsByNameVisitor(name)
-               v.enter_visit(self)
-               return v.result
-       end
-end
-
-private class CollectTokensByTextVisitor
-       super Visitor
-       var text: String
-       init(text: String) do self.text = text
-       var result = new Array[Token]
-       redef fun visit(node)
-       do
-               node.visit_all(self)
-               if node isa Token and node.text == text then result.add(node)
-       end
-end
-
-private class CollectAnnotationsByNameVisitor
-       super Visitor
-       var name: String
-       init(name: String) do self.name = name
-       var result = new Array[AAnnotation]
-       redef fun visit(node)
-       do
-               node.visit_all(self)
-               if node isa AAnnotation and node.n_atid.n_id.text == name then result.add(node)
-       end
-end